biology for grade 7

The Plant kingdom was initially classified as follows fig. 7.6 - Classification of Kingdom Plant..

This phase involves the contraction of the 2 auricles, pushing the blood into the respective ventricles. There is no back flow of blood due to the presence of the bicuspid and the tricuspid valves. The atrial systole takes 0.1 second. This is followed by the atrial diastole when both the auri..

Lead and zinc are mainly located in Rajastan, Gujarat, Maharastra, West Bengal, Orisaa, Uttar Pradesh, Madhya Pradesh and Tamil Nadu. Total recoverable reserves of lead and zinc ores are 177 million tons, which can yield 23.80 lakh tons of lead and 9.7 million tons of zin..

1. Leaves show chlorosis. 2. Reduction in juice content of citrus fruits. 3. Fruit formation, in general is retarded. 4. "Tea yellow" in tea plant. 5. Premature germination of lateral buds, killing of young branches. 6. Smaller and chlorotic leaves. 7. Necrosis of leaf margin and tip. 8. ..

Pancreas are present at the end of the duodenum. It secretes pancreatic juice which has an almost neutral pH (6 to 7). Pancreatic juice consists of enzymes like the pancreatic amylase (to act on carbohydrates), trypsin (to act on proteins) and lipase (to act on lipids and fats). This jui..

The animal kingdom was initially classified as follows: fig. 7.8 - Classification of Kingdom Animal..

The value of RQ is equal to 1 if carbohydrates are the respiratory substrates in aerobic respiration...

1) Indiscriminate deforestation should be prohibited. 2) Wastage of timber and fuel wood to be avoided. 3) Alternative sources of energy, such as biogas should be used to supplement fuel wood. 4) Forest fires should be prevented. 5) Pests and diseases of the forest trees should be controlled chemi..

Flora refers to plant species and fauna refers to animal species. The term biota includes both plant as well as the domesticated and wild species of animals. Our country has a rich diversity of flora and fauna. There are over 45,000 plant species and 81,251 animal species. It represents about ..

Once an organism is identified and grouped, it is then described in terms of the various taxonomic categories to which it belongs. Such a description is known as systematic position . The following is a description of the systematic position of human being and the hibiscus plant. fig. 7.5..